We often need to add a fixed text or html element to the text of all posts: a signature, a link, a little logo, even a form. In fact, there are some ways to do this task but perhaps the easiest way is to use the the_content filter.

The the_content filter –in general any WordPress filter– is a kind of funnel through which WordPress passes the post_content before being displayed on screen. Using this funnel (filter), ie, adding operations inside it, we can change de content of the post_content field for all Posts but for doing this we have to do two operations. Continue reading…